code: def download_file(self, bucket: str, key: str, path: str) -> None:
      with open(path, "w") as fp:
          fp.write(self.objects[(bucket, key)])
  
file_path: determined/harness/tests/s3.py
imports: from typing import Any, Dict, List, Tuple
  import boto3.exceptions
label_desc: Use image node_id 4 for calling the MockS3Client obj's underlying member method code with example usage: obj.download_file(bucket, key, path) without return types